The '''United States Department of War''', also called the ''War Department'' (and occasionally ''War Office'' in the early years), was the United States Cabinet
department originally responsible for the operation and maintenance of the United States Army
. The War Department also bore responsibility for naval affairs until the establishment of the United States Department of the Navy|Navy Department
in 1798 and for most land-based air forces until the creation of the United States Department of the Air Force|Department of the Air Force
The United States Secretary of War|Secretary of War
headed the war department throughout its existence. The Secretary of War, a civilian with such responsibilities as finance and purchases and a minor role in directing military affairs, headed the War Department.
The War Department existed from 1789 until September 18, 1947, when it split into United States Department of the Army|Department of the...